Notes by Andreas Henriksson on 2006-06-26 about the Atheros WLAN mess.

This is an attempt to summarize the history of some of the attempts to
bring an open source Atheros WLAN driver to Linux. I may have
completely missed something so, please!, don't treat this as any facts.
It's just my personal reflection and nothing else.

Reyk Floeter[1] started one of the first successful attempts at reverse
engineering the closed source HAL distributed with MadWifi[2]. His work
was merged into a fully open source driver in OpenBSD[3].
When there was discussions about porting the reverse engineered HAL to
Linux some people started to say that the openbsd HAL was not properly
reverse engineered but code was directly stolen[4] from Atheros, which
license their code to third parties.

Even if this would not be the case, the design of having a separate HAL
probably wasn't good enough code quality to be merged into the Linux
kernel (which has very strict coding style rules) anyway.
A separate project, ath-driver[5], emerged to create a cleanly written
driver for Atheros wlan was started. The project claimed to have
separately reverse engineered and not based on the OpenBSD HAL. 
Yet more questions[6] was raised about this project not being
legitimate either, and finally a cleanroom reverse engineering method
seemed to get started[7], but after that date not much has been heard
from any of the projects to bring opensource atheros support to Linux.

New vage promises[8][9] shows up from time to time but no code seem to
appear that will move Linux closer to having native, opensource,
Atheros WLAN drivers.

To this date the www.ath-driver.org code seems to be the most
promising completely opensource codebase, but being unfinished and
not cleanroom reverse engineered, not much hope are left for it to
actually become a driver which gives Linux support for Atheros WLAN
out of the box.

[1] http://team.vantronix.net/ar5k/
[2] http://madwifi.sf.net
[3] http://www.openbsd.org/cgi-bin/cvsweb/src/sys/dev/ic/ar5xxx.h
[4] http://zgp.org/pipermail/linux-elitists/2005-June/011192.html
[5] http://www.ath-driver.org/
[6] http://lists.gnumonks.org/pipermail/ath-driver-devel/2006-February/000164.html
[7] http://lists.gnumonks.org/pipermail/ath-driver-devel/2006-March/000184.html
[8] http://www.linuxworld.com.au/index.php/id;1438810132;fp;2;fpid;1
[9] http://lists.gnumonks.org/pipermail/ath-driver-devel/2006-July/000371.html




More relevant links:
http://en.wikipedia.org/wiki/Comparison_of_Open_Source_Wireless_Drivers
http://kerneltrap.org/node/4118
http://kerneltrap.org/node/4818
http://kerneltrap.org/node/6692
http://www.devicescape.com/news/releases/release_05-01-06_opensource.php
http://kernel.org/git/?p=linux/kernel/git/linville/wireless-dev.git;a=shortlog



Please send corrections, feedback, links and other relevant information
about the Atheros history to me: andreas@fjortis.info